Collateral risk

President Trump’s vow to heavily bomb Islamic State extremists portended costs that could be growing clearer in Mosul, where a U.S. air strike this month is suspected of causing one of the worst civilian slaughters of America’s long Iraq entanglement. With 275 more U.S. troops reportedly headed to the region, escalation is nevertheless afoot.

U.S. Central Command has acknowledged and opened an investigation into a March 17 air strike in the vicinity of a ruined home where more than 100 Iraqis died. Meanwhile, the fight to remove the Islamic State from Mosul paused last weekend amid condemnation of the toll of a week of U.S.-led bombardment supporting Iraqi ground forces. More of the hundreds of thousands of civilians still trapped in the city took advantage of the break in hostilities to flee for refugee camps.

The Trump administration has presided over rising civilian casualties and troop deployments in neighboring Syria, too, with scores of recent civilian deaths near a school and a mosque under investigation. Statistics gathered by the Airwars project show coalition air strikes have caused more civilian deaths in March than in any month since the campaign against the Islamic State began more than two years ago.

While Trump has yet to articulate a long-promised change in U.S. strategy against the Islamic State, the increasing carnage does reflect his contention that the Obama administration’s approach to air strikes was too careful. Certainly no one wants to be rid of Islamic State more than the unwilling subjects of its socalled caliphate, but liberation would be useless to a city ruined by its liberators.